1. Field of the Invention
The present invention relates generally to automatic liquid delivery systems and, more particularly, to a self-powered apparatus for time delayed delivery of liquid to an end-user. Specifically, the present intention relates to an automatic liquid delivery system having a time delayed release mechanism controlled by liquid evaporation rates.
2. Description of the Prior Art
Automatic liquid delivery systems in the form of time release plant watering devices are well known in the art. Such devices are generally designed to meter out water to a plant on a gradual or timed basis or upon certain soil conditions as measured by the device. The purpose of such devices is to enable plants to be watered on a regular basis automatically without requiring constant human monitoring. Moreover, such devices are quite useful for watering household plants during a period of time when the household is vacant, such as when one is on a vacation or the like. Unfortunately, such devices tend to be somewhat complex in nature and construction.
U.S. Pat. No. 3,856,205, No. 4,542,762 and No. 5,956,899 all disclose automatic liquid delivery systems that include soil-monitoring sensors which detect soil moisture level. These devices are constructed so that when the soil monitor determines that the moisture level in the soil has fallen below a pre-established level, the device then adds water to the plant soil.
U.S. Pat. No. 4,846,206 teaches an automatic liquid delivery device for watering one or more plant locations using siphoning action as opposed to gravity feed. U.S. Pat. No. 5,542,605 discloses an automatic liquid dispensing device for watering plants in discrete time intervals also using siphoning action, in part. Both of these patents disclose watering system features which contain two liquid reservoirs requiring movement of liquid from one reservoir to the other in order to accomplish the desired siphoning action and timed liquid release.
As can be seen from the above, there are numerous types of systems available to accomplish automatic liquid delivery for watering plants or the like. However, all of these systems are rather complex in operation and construction. Consequently, the use of such systems tend to be expensive, difficult to set up and operate, and easy to clog or malfunction. Thus, there remains a need for a simple automatic watering device for plants or other end users which does not require outside power sources or complex monitoring devices yet enables time delayed release of water to plants or other end users.